The present invention relates to a system and method for updating and enhancing a geographic database, and more particularly, the present invention relates to a system and method for updating and enhancing a geographic database based on feedback from field use of the geographic data.
Computer-based navigation systems for use on land have become available in a variety of forms and for a variety of applications. One exemplary type of system uses a geographic data set, a navigation application, and optionally, a positioning system. The geographic data set includes information about the positions of roads and intersections in or related to a specific geographical area, and may also include information about one-way streets, traffic signals, stop signs, turn restrictions, street addresses, alternative routes, hotels, restaurants, museums, stadiums, offices, automobile dealerships, auto repair shops, etc.
The optional positioning system may employ any of several well-known technologies to determine or approximate one's physical geographic location. For example, the positioning system may employ a GPS-type system (global positioning system), a "dead-reckoning"-type system, or combinations of these, or other systems, all of which are known in the art.
The navigation application portion of the navigation system is a software program that uses the detailed geographic data set and the positioning system (when employed). The navigation application program may provide the user with a graphical display (e.g. a "map") of a specific location in the geographical area. The navigation application may provide the user with data indicating his own location and specific directions to locations in the geographical area from wherever he is located.
Computer-based navigation systems may exist as a single unit that may be installed in a vehicle, or even carried by persons. The navigation application and geographic data set may be provided as software products that are sold or licensed to users to load in personal computers. Systems operating on personal computers may be stand-alone or connected by a communication link to a central or regional system. Organizations, such as trucking companies, package delivery services, and emergency dispatch units may employ navigation systems to track fleets and ensure the quickest routes to destinations. The navigation systems may also be made available on-line from a central system to multiple users on an "as needed" basis, or from on-line services such as services available on the Internet and private dial-up services.
Individual users can use navigation systems to obtain directions to a desired destination thereby reducing travel time and expenses. The directions can include detours around construction delays. Directions may be provided to street addresses, intersections, or to entities by name, such as to restaurants, hotels and service stations.
One potential obstacle to providing enhanced features with a navigation system is the difficulty in maintaining up-to-date information in the geographic data set . A publisher of geographic data may obtain the information that becomes part of geographic data sets from field personnel sent to the locations to record the information or from aerial photographs or municipal records or other sources. Geographic information, however, becomes outdated as new roads are built, existing roads are changed, traffic signals are installed, businesses change their hours of operation, new businesses open, existing businesses close, etc. When changes occur, data in the geographic data set becomes inaccurate and its utility is thereby lessened.
Information identifying changes are collected using the same techniques as described above. Once the information regarding changes is collected, it is incorporated into a master geographic data set. The publisher of geographic databases then periodically distributes updated geographic data reflecting the changes to end-user. However, the process of acquiring information regarding changes is time-consuming and expensive. Moreover, existing methods of acquiring updated data may become increasingly expensive as geographic databases become more detailed and extensive in scope.
Another limitation with existing methods of data acquisition is accuracy. Even with high quality aerial photographs and other existing collection methods, the geographic coordinates of features may not always be entered in the database with a high level of precision. While existing methods are generally adequate to provide geographic data of sufficient accuracy for vehicle positioning in route guidance applications, greater geographical accuracy may be required for certain other applications, such as vehicle control.
Accordingly, a system and method are desired that would provide for a more efficient acquisition of information reflecting changes and corrections in geographic areas to navigation systems. Further, a system and method are desired that allow the accuracy of the data in a geographic database to be enhanced.